> Most common issue is power supply. When a board isn't designed to
> be flashed this way, voltage may leak to other components on the
> mainboard. Hence board-specific documentation is so important.
> Measuring voltage when trying to access the flash may give a clue.
>
> Without documentation it's best not to apply voltage via the flash
> programmer (RPi in your case), in case you were trying this. Better
> is to use the board's regular power supply and making sure that it
> doesn't boot (i.e. stays in a soft-off / S5 state). And *not* connec-
> ting VCC to pin8. Again, measuring voltage at the flash chip.
>
> That it's a WSON chip also doesn't make things easy. Did you solder
> something and can confirm connectivity? or how do you connect to the
> flash chip?
I got a WSON-8 8x6 probe. It has to be held down on the chip by hand so
there is no way for me to measure voltage at the same time. I have
tried the following configurations with my RPi:
No pw supply connected to mainboard - pins 1-8 connected between RPi
and chip. Results= RPi reboots as soon as probe is placed on the chip
No pw supply connected to mainboard - all pins connected except pins 3
and 7. Result= chip not detected
Pw supply connected to mb, S5 soft off - all pins connected except pin
8. Result= chip not detected
To enter S5 I power on the chromebox, then power off using power
button. I tried reading voltage at the BIOS chip while power is
connected to MB in S5 soft off. I don't get any voltage reading while
connected to pin 4 GND and any other pin, or pin 8 VCC while connected
to any other pin. This doesn't make sense to me. I think the chip
should have power when the MB has power. I am just using a regular
multimeter with nothing soldered to the board, just reading with needle
tip probes.
